Session: 05-09: Fluid Structure Interaction

Paper Number: 122518

122518 - Numerical Investigation of the Kinematics of the Flexible Composite Wedge in Water Entry Experiments Based on Coupled CFD-FEA Approach 

Numerical Investigation of the Kinematics of the Flexible Composite Wedge in Water Entry Experiments Based on Coupled CFD-FEA approach. By Subodh Chander, Cherith Lavisetty, Surabhi Srivastava & Stefano Brizzolara

Water entry is a complex non-linear phenomenon which involves multiphase interaction, and has been of interest in various engineering fields. For example, high speed craft slamming in rough sea, where the craft is frequently launched off the wave and lands on the air-water interface at high impact velocity.

Lately, with the use of lightweight material such as composites, makes the effects of hydro elasticity even more crucial for the structural design of the craft. Although there are existing design codes for the design of high speed crafts by various classification societies but this complex phenomenon is not yet incorporated and need to be accessed via direct calculations.

In this paper, the effects of hydro elasticity on the composite plate are studied using computational methods. The results from the experimental study of “Free-Falling Wedge with the composite bottom plate” conducted by or Javaherian et al. (2022) were used for the numerical validation. The computational fluid dynamic model with fluid structure interaction was used to replicate the experimental setup with pressure and displacement probes located in accordance with the experimental design. The magnitude of pressure and displacements of the bottom flexible plate obtained from the numerical model were compared with the experimental data. To study the effects of fluid-structure interaction a non-dimensional number, quantifying the hydro elasticity of the wedge plate, proposed by Faltinsen (1999) was used. Values of R less than 2 are considered flexible and the fluid pressure is modified due to the structural deflection. The R value for the flexible composite plate used in this study was 0.064.

The numerical results show good qualitative and quantitative agreement with the experimental data, in terms of kinematics, such as vertical velocity, displacement, acceleration as well as dynamic quantities such as pressure and structural response which are plotted in terms of a 3D deformed shape of the plate. The data was analyzed for three time steps 8.5miliseconds, 16miliseconds and 23.5miliseconds, respectively. The maximum deformation of 4.35mm was noted at t=16ms.

Presenting Author: Subodh Chander Virginia Tech